Vitamin , cyanocobalamin, is essential for human nutrition. it is concentrated in animal tissue but not in higher plants. although nutritional requirements for the vitamin are quite low, people who abstain completely from animal products may develop a deficiency anemia. cyanocobalamin is the form used in vitamin supplements. it contains 4.34% cobalt by mass. calculate the molar mass of cyanocobalamin, assuming that there is one atom of cobalt in every molecule of cyanocobalamin.

1360.0 g/mol

Explanation:

If there is one atom of cobalt in every molecule of cyanocobalamin its chemical formula must be

CoX₂, so there is 1 mol of cobalt for 1 mol of the compound. The molar mass of the cobalt is 59 g/mol. So, there is 59 g of cobalt in 1 mol of the cyanocobalamin and it represents 4.34% of the total mass, so:

0.0434m = 59

m = 1359.45 g of cyanocobalamin

The molar mass of the molecule is the mass divided by the number of moles (which is 1), so it is:

M = 1359.45 g/mol = 1360.0 g/mol

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles

it is stable as it is in group 0 which have full outer shells of electrons